Ashwagandha root benefits, side effects, dosage, review and supplement Information - Influence of this herb on brain, thyroid, sexuality, relaxation and sleep, how often to use and interactions, by Ray Sahelian, M.D.

Ashwagandha herb - also known as Indian winter cherry - is a shrub cultivated in India and North America whose roots have been used for thousands of years by Ayurvedic practitioners. The root contains flavonoids and many active ingredients of the withanolide class. Several studies over the past few years have looked into whether this herb has anti-inflammatory, anti-tumor, anti-stress, antioxidant, mind-boosting, immune-enhancing, and rejuvenating properties (see studies at bottom of page). Historically ashwagandha root has also been noted to have sex-enhancing properties. Many people notice a relaxing effect within hours of taking a 500 mg pill.

Anti-anxiety herb
The roots of ashwagandha are used extensively in Ayurveda, the classical Indian system of medicine. In rodent studies the herb has been shown to reduce anxiety and have a positive effect on mood.

Do you know whether this herb can act as a stimulant (e.g., in the manner of some forms of ginseng)? I recently tried using ashwagandha to help treat my anxiety and depression, and found that my symptoms may have been exacerbated by its use. I experienced a “wired, edgy” feeling that intensified my feelings of anxiety and depression.
    This could be dose dependent. We have learned that high dosages of ashwagandha can cause a feeling of being restless, but you may try a third of a capsule and this way you may notice more of the relaxing effect rather than the stimulation effect. Another option is to use plain herb as opposed to a concentrated extract.

Antibacterial research studies
Antibacterial efficacy of Withania somnifera an indigenous medicinal plant against experimental murine salmonellosis.
Phytomedicine. 2005 Mar.
We evaluated the antibacterial activity of ashwagandha root and leaves, against pathogenic bacteria. Both aqueous as well as alcoholic extracts of the plant (root as well as leaves) were found to possess strong antibacterial activity against a range of bacteria including Salmonella typhimurium. Moreover, in contrast to the synthetic antibiotic (viz. chloramphenicol), ashwagandha extracts did not induce lysis on incubation with human erythrocytes, advocating their safety to the living cells. Finally, the antibacterial efficacy of the ashwagandha extracts isolated from plant (both root and leaves) was determined against experimental salmonellosis in Balb/C mice. Oral administration of the aqueous extracts successfully obliterated salmonella infection as revealed by increased survival rate as well as less bacterial load in various vital organs of the treated animals.

Athletics and exercise performance
Forty elite Indian cyclists were chosen randomly and were equally divided into experimental and placebo groups. The experimental group received 500 mg capsules of aqueous roots of Ashwagandha twice daily for eight weeks, whereas the placebo group received starch capsules. There was significant improvement in the experimental group in all parameters, namely, VO(2) max, METS, and time for exhaustion on treadmill in comparison to the placebo group which did not show any change with respect to their baseline parameters. J Ayurveda Integr Med. 2012. Effects of eight-week supplementation of Ashwagandha on cardiorespiratory endurance in elite Indian cyclists. Faculty of Sports Medicine and Physiotherapy, Guru Nanak Dev University, Amritsar, Punjab, India.

Blood sugar
One small study found ashwagandha root was able to reduce blood sugar and cholesterol levels, and had a diuretic effect.

Brain health
Ashwagandha is used in India to treat mental deficits in geriatric patients, including amnesia. Researchers from the University of Leipzig in Germany wanted to find out which neurotransmitters were influenced by the herb. After injecting some of the chemicals in ashwagandha into rats, they later examined slices of their brain and found an increase in acetylcholine receptor activity. The researchers say, "The drug-induced increase in acetylcholine receptor capacity might partly explain the cognition-enhancing and memory-improving effects observed in animals and humans."
   A study done in 1991 at the Department of Pharmacology, University of Texas Health Science Center indicated that extracts of ashwagandha had GABA-like activity. This may account for this herb’s anti-anxiety effects.
   A 2002 laboratory study indicates ashwagandha extract stimulates the growth of axons and dendrites. A 2001 study in rodents showed the extract had memory boosting ability. A 2000 study with rodents showed it to have anti-anxiety and anti-depression effects.

Cancer
Withaferin A is a potent inhibitor of angiogenesis (new blood vessel growth). Angiogenesis 2004.

Growth inhibition of human tumor cell lines by withanolides from ashwagandha leaves.
Life Sci. 2003.
The leaves of ashwagandha are used in the treatment of tumors and inflammation in several Asian countries. We have isolated twelve withanolides from the leaves of this species. Compounds were tested for their anti-proliferative activity lung, colon, central nervous system and breast human tumor cell lines. Withaferin A and its derivatives exhibited inhibitory concentrations. Viscosalactone B showed the 50% inhibition. Therefore, incorporation of ashwagandha in the diet may prevent or decrease the growth of tumors in human.

Diabetes and high blood sugar
Hypoglycemic, diuretic and hypocholesterolemic effect of winter cherry root.
Indian J Exp Biol. 2000.
Hypoglycemic, diuretic and cholesterol lowering effects of roots of ashwagandha were assessed on human subjects. Six mild non insulin dependent subjects and six mild high cholesterol subjects were treated with the powder of roots of ashwagandha for 30 days. Decrease in blood glucose was comparable to that of an oral hypoglycemic drug. Significant increase in urine sodium, urine volume, significant decrease in serum cholesterol, triglycerides, LDL (low density lipoproteins) and VLDL (very low density lipoproteins) cholesterol were observed indicating that this plant is a potential source of hypoglycemic, diuretic and hypocholesterolemic agents.

Heart attack
Cardioprotection from ischemia and reperfusion injury by ashwagandha
Mol Cell Biochem. 2004.
Ashwagandha on chronic administration markedly augmented antioxidants (glutathione, glutathione peroxidase, superoxide dismutase, catalase) while Vitamin E did not stimulate the synthesis of endogenous antioxidants compared to sham. Results indicate that it significantly reduced myocardial injury and emphasize its beneficial action as a cardioprotective agent.

Lymphoma
Anticarcinogenic activity of Withania somnifera against Dalton's Ascitic Lymphoma.
J Ethnopharmacol. 2004.
The effect of ethanolic extract of ashwagandha root against Dalton's Ascitic Lymphoma has been evaluated in Swiss albino mice. A significant increase in the life span and a decrease in the cancer cell number and tumour weight were noted in the tumour-induced mice after treatment. These observations are suggestive of the protective effect of ashwagandha extract in Dalton's Ascitic Lymphoma.

Nerve cell growth
Axon- or dendrite-predominant outgrowth induced by constituents from ashwagandha.
Neuroreport. 2002.
We previously reported that the methanol extract of Ashwagandha (roots of Dunal) induced dendrite extension in a human neuroblastoma cell line. In this study, we found thatcompounds isolated from the methanol extract enhanced neurite outgrowth in human neuroblastoma SH-SY5Y cells.

Nitric oxide production
Induction of nitric oxide synthase expression by ashwagandha in macrophages.
Life Sci. 2003.
Ashwagandha may induce the synthesis of inducible nitric oxide synthase expression likely by acting at transcriptional level. The increased nitric oxide production by macrophages could account, at least in part, for its immune stimulating properties.

OCD, obsessive compulsive disorder
Extracts of ashwagnadha root given to mice were comparable in efficacy to standard fluoxetine medication treatment. Influence of Withania somnifera on obsessive compulsive disorder in mice. Asian Pac J Trop Med. 2012.

Ashwagandha side effects, safety, risk, danger
Ashwagandha herb does not seem to have any significant side effects but long term studies are not yet available to determine ashwagandha side effects from chronic use. Nevertheless, it is best to take breaks from use. For instance, one can take a week off each month or take it 3 or 4 times a week as opposed to daily. There is one case report from Holland of a person taking high doses for prolonged periods who ended up with excessive thyroid hormone production.

Effect on thyroid gland
My name is Rudger Hogeveen, from Netherlands. am a medical student in Holland. Recently I read an article in a Dutch medical journal regarding ashwagandha and thyroid gland. In this journal was a case report about an patient who had thyrotoxicosis after chronic ashwagandha supplement use.
Ned Tijdschr Geneeskd. 2005: Thyrotoxicosis following the use of ashwagandha.
A 32-year-old healthy woman developed thyrotoxicosis while taking capsules that contained ashwagandha herbal extract for symptoms of chronic fatigue. She was not taking any other remedies or medications. During the first few weeks, she took the capsules only occasionally without any symptoms, but after increasing the dose, she experienced clinical symptoms indicative of thyrotoxicosis. This was confirmed by laboratory assessment. The symptoms resolved spontaneously after discontinuation of the ashwagandha capsules and laboratory values normalised. Data from animal studies, however, have suggested that ashwagandha can increase serum concentrations of thyroid hormones. This case study suggests that excess thyroid hormone effects is a potentially serious side effect of ashwagandha. Note: Rudger Hogeveen approved his name being mentioned.

I have been suffering from a thyroid condition for several years and am taking Synthroid with some benefit, but still am symptomatic despite lab levels which are in the target range. An herbal specialist who recommended ashwahgandha. I did feel significantly better on this supplement, my hair loss stopped, my libido returned, etc, however, I am experiencing some problems with symptoms of increased thyroid production. Because I am finally feeling better/normal for the first time in years, I would like to find a way to perhaps taper my Synthroid and stay on the ashwagandha (since it may enhance thyroid hormone production). my current endocrinologist knows nothing about herb / Ayurvedic medicine.
   The influence of ashwagandha on thyroid function is still being evaluated and there is very little research on the topic, including what the appropriate dosage would be for the long term and how such supplements interact wish Synthroid or other thyroid medications.

I started taking ashwagandha capsules for the past 2 months. Last year I got my T3, T4, TSH tested and they were all normal. And now when tested again T3, T4, Ft4 are all normal but TSH is abnormal 13.9. I don't have any symptoms of hypothyroidism and still my blood reports TSH have come out positive. When consulted doctors, they asked me to get on medication Thyronorm 50mg for now. I read that ashwagandha can cause hyperthyroidism. My family has no background of any thyroid dysfunction. All of a sudden I have TSH elevated to high level and this is bothering me a lot. Now my doubt is can ashwagandha also cause hypothyroidism ? Should I stop taking the capsules. Also should I start medication for hypothyroidism or wait for now.
    I can't give specific treatment advice but your doctor may wish to read this page.

I have Hashimoto's thyroiditis and when I began the herbal product I was hyperthyroid. After a couple days I felt better, much calmer, more relaxed. I did have to make a slight increase in my Methimazole (anti-thyroid medication) to compensate for what I thought was the mild thyrotoxic effects of ashwagandha. After about 6 weeks of continued daily use, my thyroid blew up. I could not sleep, and had all of the symptoms of severe hyperthyroidism. I had forgotten about the herb's potential to cause thyrotoxicosis, but "re-discovered" it, and stopped. I had to take very high doses of the Methimazole while experiencing the thyrotoxicosis. Once I stopped the ashwaganda, my thyroid appeared to normalize to its previous state after about 5 days. Then after another few days, it went very hyper once again. It did finally settle down to the normal range after a couple of weeks as confirmed by blood tests. It is now a couple months later, and I am borderline hyperthyroid. I am just letting you know, so you can warn others about ashwaganda and the danger it can present. I want to also state that your website is very informative and actually was the site that made me recall that ashwaganda can cause thyrotoxicosis. I feel that the information provided is great because it promotes a cautious approach when using supplements, as there have not been adequate studies on them. You are doing a great service for the public.

I find it very interesting and trustworthy to read about various supplements on your site. I have had some mild anxiety and mood disturbances for a while so i decided to try ashwagandha 300 mg of the whole herb, not an extract. I have read on your page that it can interfere with thyroid function. When i have been to the doctor before i asked to have my thyroid checked. I had a normal TSH and a T4 that was in the high normal range. I really want to take this herb. Obviously i am not hyperthyroid since tests are normal and symptoms are non existent. So my question is it so powerful that 300 mg of the whole herb per day can make the thyroid go hyperthyroid?
   It is unlikely that small amounts of the herb will have a strong influence on thyroid hormone levels, but it is difficult to predict in any one individual what would occur.

Botany
Ashwagandha herb grows in India, Pakistan, India Sri Lanka and in parts of Africa. The name is derived from Sanskrit words and means 'horse smell' due to the fact that the plant's root has the odor of a sweaty horse.

Interactions with dietary supplements
Can ashwagandha and St. John's wort be taken together?
    In most cases if the dosages are low, yes. However each person is different and it depends what other medications you may be taking, your overall health, age, and other factors. It is best to learn how each one works for you by itself before combining.

Interactions with medications
Can you please tell me if is compatible with Azilect, Amantadine, Carbidopa, Pramipexole? I have Parkinson's and don't sleep and wanted to try the herb.
   I have not seen any studies with these combinations. As a general rule it is a good idea to begin with a portion of a tablet or capsule when first trying a new supplement while taking medications and to inform one's health care provider.